The present invention relates to electric vehicles. The present invention also relates to control systems and methods for electric vehicles.
An electronic traction vehicle is a vehicle that uses electricity in some form or another to provide all or part of the propulsion power of the vehicle. This electricity can come from a variety of sources, such as stored energy devices relying on chemical conversions (batteries), stored electrical charge devices (capacitors), stored energy devices relying on mechanical stored energy (e.g. flywheels, pressure accumulators), and energy conversion products. In a typical conventional electric traction vehicle, a prime mover, such as a diesel engine, is used to drive an electric generator or alternator which supplies electric current to one or more traction motors. The traction motors typically are coupled to wheel sets on the vehicle. A typical vehicle that utilizes this type of electric traction is a railroad locomotive. In some conventional electric traction vehicles, stored energy is used to provide the main power which provides the electrical current to one or a plurality of traction motors. A typical vehicle that utilizes this type of electric traction is a golf cart or battery powered electric car. In some conventional electric traction vehicles, having more than one sources of energy is desirable. By having more than one source of energy, some optimizations in the design can allow for more efficient power production, thus allowing power to be used from different sources to come up with a more efficient system for traction. These types of vehicles are commonly referred to as hybrid electric vehicles (HEV). Series and Parallel HEV system designs are what is usually encountered.
A master controller is often used to control the overall system and give command signals to the engine, generator/alternator, prime mover energy conversion (AC to DC) stored energy conversion, and/or traction level energy conversion (DC to AC). This controller architecture requires a highly integrated control strategy. It also provide a single point of failure for the traction system.
Thus, there is a need for an electric traction vehicle that is modular in design and control. There is also a need for electric traction vehicle that can be updated and upgraded as new technology and components become available without a required redesign of the overall vehicle system. There is also a need for improved control systems and methods for electric vehicles, and systems and methods for servicing, repairing and monitoring electric vehicles.